| 摘要 |
1,258,982. Cross-linking polymers. RAYCHEM CORP. 28 Aug., 1969 [30 Aug., 1968], No. 42933/69. Heading C3P. Polymers containing carbon atoms and -NO 2 groups, each NO 2 group being attached to a carbon atom and the polymer being such that the -NO 2 groups introduce active sites into it are cross-linked by reacting with a polyisocyanate, optionally in the presence of apolyfunctional active hydrogen compound and/or a catalyst. The polymer may be in the solid state and may be contacted with polyisocyanate in the vapour state and the treated polymer cross-linked at elevated temperature, or the polymer may be contacted with polyisocyanate in the liquid state and the treated polymer contacted with active hydrogen compound. The polymer may be a polymer or copolymer of ethylene, butene-1, vinyl acetate, ethyl acrylate or cetyl acrylate, nitrated by reaction with nitrogen dioxide or fuming nitric acid. Specified polyisocyanates are 4-methyl-m-phenylene diisocyanate, methylenedi-p-phenylene diisocyanate, polymethylene polyphenyl isocyanate, hexamethylene diisocyanate, bitolylene diisocyanate and dianisidine diisocyanate. Specified active hydrogen compounds are polyfunctional alcohols and amines and water. Specified catalysts are organic metallic compounds and tertiary amines. Examples describe the nitrating of (1, 3 and 4) polyethylene, (2) ethylene/vinyl acetate copolymer and (5) ethylene/ethyl acrylate copolymer, and the cross-linking of nitrated polyethylene with (6, 8, 9, 18 and 21) hexamethylene diisocyanate; (7 and 22) methylene-di-p-phenylene diisocyanate and water; (10) bitolylene diisocyanate together with (11) ethylene glycol or hexamethylene diamine and (13, 14 and 19) water; (12) water and methylene-di-p-phenylene diisocyanate, hexamethylene diisocyanate, dianisidine diisocyanate, bitolylene diisocyanate or 4-methyl-m-phenylene diisocyanate; and (21) hexamethylene diisocyanate or methylene-di-pphenylene diisocyanate; the use of bitolylene diisocyanate and water to cross-link nitrated (15) ethylene/ethyl acrylate copolymer, (16) ethylene/vinyl acetate copolymer and (17) polybutene; and of 4-methyl-m-phenylene diisocyanate to cross-link a mixture of nitrated polyethylene and nitrated ethylene/ethyl acrylate copolymer; optionally in the presence of catalysts and compounding ingredients such as chlorinated paraffin wax, Diels Alder adduct of 2 moles of hexachlorocyclopentadiene and 1 mole of cycloocta-1,5-diene, antimony oxide, carbon black, magnesium oxide, magnesium silicate and 4,4<SP>1</SP>-thio bis(6-t-butyl-m-cresol). The polymers may be made into shaped articles, e.g. syringes, wire coating and tubes, to which heat recovery properties may be imparted. |
